docs: def _get_stress_drop_scaling_factor(self, magnitude):
          """
          Returns the magnitude dependent stress drop scaling factor defined in
          equation 6 (page 1128) of Atkinson & Boore (2011)
          """
          stress_drop = 10.0 ** (3.45 - 0.2 * magnitude)
          cap = 10.0 ** (3.45 - 0.2 * 5.0)
          if stress_drop > cap:
              stress_drop = cap
          return log10(stress_drop / 140.0) / log10(2.0)